CN107767814B - Pixel circuit, display device and double-gate driving transistor - Google Patents

Pixel circuit, display device and double-gate driving transistor Download PDF

Info

Publication number
CN107767814B
CN107767814B CN201711204071.3A CN201711204071A CN107767814B CN 107767814 B CN107767814 B CN 107767814B CN 201711204071 A CN201711204071 A CN 201711204071A CN 107767814 B CN107767814 B CN 107767814B
Authority
CN
China
Prior art keywords
driving transistor
transistor
double
control unit
electrically connected
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201711204071.3A
Other languages
Chinese (zh)
Other versions
CN107767814A (en
Inventor
冯雪欢
袁志东
蔡振飞
李蒙
袁粲
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BOE Technology Group Co Ltd
Hefei Xinsheng Optoelectronics Technology Co Ltd
Original Assignee
BOE Technology Group Co Ltd
Hefei Xinsheng Optoelectronics Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BOE Technology Group Co Ltd, Hefei Xinsheng Optoelectronics Technology Co Ltd filed Critical BOE Technology Group Co Ltd
Priority to CN201711204071.3A priority Critical patent/CN107767814B/en
Publication of CN107767814A publication Critical patent/CN107767814A/en
Priority to US15/981,020 priority patent/US10777128B2/en
Application granted granted Critical
Publication of CN107767814B publication Critical patent/CN107767814B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G09G3/3225—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G09G3/3225—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
    • G09G3/3233—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the current through the light-emitting element
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K10/00—Organic devices specially adapted for rectifying, amplifying, oscillating or switching; Organic capacitors or resistors having potential barriers
    • H10K10/40—Organic transistors
    • H10K10/46—Field-effect transistors, e.g. organic thin-film transistors [OTFT]
    • H10K10/462—Insulated gate field-effect transistors [IGFETs]
    • H10K10/481—Insulated gate field-effect transistors [IGFETs] characterised by the gate conductors
    • H10K10/482—Insulated gate field-effect transistors [IGFETs] characterised by the gate conductors the IGFET comprising multiple separately-addressable gate electrodes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/10—OLED displays
    • H10K59/12—Active-matrix OLED [AMOLED] displays
    • H10K59/125—Active-matrix OLED [AMOLED] displays including organic TFTs [OTFT]
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0819—Several active elements per pixel in active matrix panels used for counteracting undesired variations, e.g. feedback or autozeroing
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0842—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor
    • G09G2300/0852—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor being a dynamic memory with more than one capacitor
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0262—The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/08—Details of timing specific for flat panels, other than clock recovery
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0233—Improving the luminance or brightness uniformity across the screen
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/029—Improving the quality of display appearance by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
    • G09G2320/0295—Improving the quality of display appearance by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel by monitoring each display pixel
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/04—Maintaining the quality of display appearance
    • G09G2320/043—Preventing or counteracting the effects of ageing
    • G09G2320/045—Compensation of drifts in the characteristics of light emitting or modulating elements
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K10/00—Organic devices specially adapted for rectifying, amplifying, oscillating or switching; Organic capacitors or resistors having potential barriers
    • H10K10/80—Constructional details
    • H10K10/82—Electrodes

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Control Of El Displays (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

The invention discloses a pixel circuit, a display device and a double-gate driving transistor, wherein the pixel circuit comprises: the threshold voltage compensation unit is respectively and electrically connected with the data end and the first control end of the external control unit, and the first grid electrode and the source electrode of the double-grid driving transistor; the mobility compensation unit is respectively electrically connected with a detection signal end and a second control end of the external control unit and a source electrode of the double-gate driving transistor; and the light-emitting control unit is respectively electrically connected with the data end and the third control end of the external control unit, the second grid electrode and the source electrode of the double-grid driving transistor and the light-emitting device, and the external control unit controls the threshold voltage compensation unit and the mobility compensation unit so as to perform threshold voltage compensation on the double-grid driving transistor and controls the mobility compensation unit and the light-emitting control unit so as to perform mobility compensation on the double-grid driving transistor and control the light-emitting device to emit light. Thus, threshold voltage compensation and mobility compensation for the driving transistor can be simultaneously achieved.

Description

Pixel circuit, display device and double-gate driving transistor
Technical Field
The present invention relates to the field of display technologies, and in particular, to a pixel circuit, a display device, and a dual gate driving transistor.
Background
Currently, with the rapid development of display panels, OLEDs (Organic Light Emitting diodes) are becoming the trend of the panel industry in the future due to their high contrast and low power consumption.
The conventional OLED pixel circuit has a 2T1C driving structure, as shown in fig. 1, but the threshold voltage and mobility of the driving transistor need to be compensated due to instability of the driving transistor. The method of compensating the threshold voltage generally includes internal compensation and external compensation, but it is very difficult to implement both the threshold voltage compensation and the mobility compensation of the driving transistor, because the mobility of the driving transistor is difficult to measure, and a complicated circuit structure or a complicated control timing is generally required.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, a first object of the present invention is to provide a pixel circuit, which can not only realize threshold voltage compensation and mobility compensation for the driving transistor at the same time, effectively improve the problem of display non-uniformity caused by threshold voltage drift and mobility variation, but also has simple and reliable compensation method.
A second object of the present invention is to provide a display device.
A third objective of the present invention is to provide a double gate driving transistor.
To achieve the above object, an embodiment of a first aspect of the present invention provides a pixel circuit, including: the light-emitting diode comprises a first power supply end, a double-gate driving transistor, a threshold voltage compensation unit, a mobility compensation unit and a light-emitting control unit, wherein the drain electrode of the double-gate driving transistor is electrically connected with the first power supply end; the threshold voltage compensation unit is electrically connected with a data end of an external control unit, a first control end of the external control unit, a first grid electrode of the double-grid driving transistor and a source electrode of the double-grid driving transistor respectively; the mobility compensation unit is electrically connected with a detection signal end of the external control unit, a second control end of the external control unit and a source electrode of the double-gate drive transistor respectively; the light-emitting control unit is electrically connected with the data end of the external control unit, the third control end of the external control unit, the second grid electrode of the double-grid driving transistor, the source electrode of the double-grid driving transistor and the light-emitting device respectively, wherein the external control unit controls the threshold voltage compensation unit and the mobility compensation unit through the data terminal, the first control terminal, the detection signal terminal, and the second control terminal, so as to perform threshold voltage compensation on the dual-gate driving transistor and control the mobility compensation unit and the light emission control unit through the detection signal terminal, the second control terminal, the data terminal and the third control terminal, so as to perform mobility compensation on the double-gate driving transistor and control the double-gate driving transistor to drive the light-emitting device to emit light.
According to the pixel circuit of the embodiment of the invention, the drain electrode of the dual-gate driving transistor is electrically connected with the first power supply end, the threshold voltage compensation unit is respectively electrically connected with the data end of the external control unit, the first control end of the external control unit, the first grid electrode of the dual-gate driving transistor and the source electrode of the dual-gate driving transistor, the mobility compensation unit is respectively electrically connected with the detection signal end of the external control unit, the second control end of the external control unit and the source electrode of the dual-gate driving transistor, and the light-emitting control unit is respectively electrically connected with the data end of the external control unit, the third control end of the external control unit, the second grid electrode of the dual-gate driving transistor, the source electrode of the dual-gate driving transistor and the light-emitting device. The external control unit controls the threshold voltage compensation unit and the mobility compensation unit through the data end, the first control end, the detection signal end and the second control end to compensate the threshold voltage of the double-gate driving transistor, controls the mobility compensation unit and the light-emitting control unit through the detection signal end, the second control end, the data end and the third control end to compensate the mobility of the double-gate driving transistor and controls the double-gate driving transistor to drive the light-emitting device to emit light. Therefore, the threshold voltage compensation and the mobility compensation of the driving transistor can be realized simultaneously, the problem of uneven display caused by threshold voltage drift and mobility change is effectively solved, and the compensation mode is simple and reliable.
In addition, the pixel circuit according to the above embodiment of the present invention may further have the following additional technical features:
according to an embodiment of the present invention, the threshold voltage compensation unit includes: a first transistor, a first electrode of which is electrically connected to the data terminal, and a control electrode of which is electrically connected to the first control terminal; and one end of the first capacitor is electrically connected with the second pole of the first transistor and the first grid electrode of the double-grid driving transistor respectively, and the other end of the first capacitor is electrically connected with the source electrode of the double-grid driving transistor.
According to an embodiment of the present invention, the mobility compensation unit includes: and a first electrode of the second transistor is electrically connected with the detection signal end, a control electrode of the second transistor is electrically connected with the second control end, and a second electrode of the second transistor is respectively electrically connected with a source electrode of the double-gate driving transistor and the other end of the first capacitor.
Further, when the first transistor and the second transistor are controlled to be turned on by the first control terminal and the second control terminal, the external control unit further outputs a first data voltage to the data terminal and outputs a first detection voltage to the detection signal terminal, so that when the first transistor and the second transistor are controlled to be turned off by the first control terminal and the second control terminal, a threshold voltage of the dual gate driving transistor is stored in the first capacitor under the combined action of the first data voltage and the first detection voltage.
According to an embodiment of the present invention, the first data voltage is greater than a threshold voltage of the dual gate driving transistor, and the first detection voltage is zero.
According to one embodiment of the present invention, the light emission control unit includes: a third transistor, a first electrode of which is electrically connected to the data terminal, and a control electrode of which is electrically connected to the third control terminal; and one end of the second capacitor is electrically connected with the second pole of the third transistor and the second grid electrode of the double-grid driving transistor respectively, the other end of the second capacitor is electrically connected with the source electrode of the double-grid driving transistor and one end of the light-emitting device, and the other end of the light-emitting device is electrically connected with a second power supply end.
Further, when the external control unit controls the second transistor and the third transistor to be turned on through the second control terminal and the third control terminal, the external control unit further outputs a second data voltage to the data terminal and keeps a first preset time, and outputs a second detection voltage to the detection signal terminal within the first preset time, and then the detection signal terminal is in a floating state, so as to charge the detection signal terminal; when the external control unit controls the second transistor and the third transistor to be disconnected through the second control end and the third control end, the external control unit also detects the charging voltage of the detection signal end, obtains the mobility according to the charging voltage, and obtains a mobility compensation value according to the mobility; when the external control unit controls the second transistor and the third transistor to be conducted through the second control end and the third control end, the mobility compensation value is written into the source electrode of the double-gate driving transistor, and third data voltage is written into the second gate electrode of the double-gate driving transistor, so that the mobility compensation is carried out on the double-gate driving transistor while the light-emitting device is controlled to emit light.
According to an embodiment of the present invention, a sum of the second data voltage and the second detection voltage is less than a voltage required for the light emitting device to emit light.
In order to achieve the above object, a display device according to a second embodiment of the present invention includes the above pixel circuit.
According to the display device provided by the embodiment of the invention, through the pixel circuit, the threshold voltage compensation and the mobility compensation of the driving transistor can be realized at the same time, the problem of uneven display caused by threshold voltage drift and mobility change is effectively solved, and the compensation mode is simple and reliable.
To achieve the above object, a third embodiment of the present invention provides a dual gate driving transistor, including: the shading metal layer is arranged on the substrate and is used as a second grid electrode of the double-grid driving transistor; a buffer layer disposed on the light-shielding metal layer and the substrate; an organic semiconductor layer disposed on the buffer layer; an insulating layer disposed on the organic semiconductor layer; a gate layer disposed on the insulating layer, the gate layer serving as a first gate of the dual gate driving transistor; a via layer disposed on the buffer layer, the organic semiconductor layer, the insulating layer, and the gate layer, the via layer including a first via and a second via; the source electrode layer and the drain electrode layer are respectively arranged on the hole punching layer, the source electrode layer is communicated with one end of the organic semiconductor layer through the first through hole, and the drain electrode layer is communicated with the other end of the organic semiconductor layer through the second through hole.
According to the double-gate driving transistor provided by the embodiment of the invention, the gate layer is used as one gate of the double-gate driving transistor, and the light-shielding metal layer is used as the other gate of the double-gate driving transistor, so that the development cost and the production cost of the double-gate driving transistor are greatly reduced, and compared with the double-gate driving transistor which is realized by two driving transistors connected in series, the double-gate driving transistor effectively reduces the structure of the whole transistor and reduces the occupied area.
Drawings
Fig. 1 is a schematic structural diagram of a conventional 2T1C pixel circuit;
FIG. 2 is a block schematic diagram of a pixel circuit according to an embodiment of the invention;
FIG. 3 is a schematic diagram of a pixel circuit according to one embodiment of the invention;
fig. 4 is a control timing chart of the pixel circuit shown in fig. 3;
FIG. 5 is a block schematic diagram of a display device according to an embodiment of the invention; and
fig. 6 is a schematic structural diagram of a double gate driving transistor according to an embodiment of the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
A pixel circuit, a display device, and a dual gate drive transistor of an embodiment of the present invention are described below with reference to the accompanying drawings. Before describing the pixel circuit of the embodiment of the present invention, a detailed description will be given of why the conventional 2T1C pixel circuit causes display unevenness due to threshold voltage drift and mobility variation.
Specifically, as shown in fig. 1, the conventional 2T1C pixel circuit includes a switching transistor M1, a driving transistor M2 and a storage capacitor Cst, wherein the switching transistor M1 is used for controlling the input of a Data voltage on a Data line Data, the driving transistor M2 is used for controlling the light emitting current of the organic light emitting diode OLED, and the storage capacitor Cst is used for providing a bias and sustain voltage for the gate of the driving transistor M2.
The 2T1C pixel circuit includes two stages within one frame time, wherein the first stage is a Data writing stage, in which the row Scan line Scan is at high level, the switching transistor M1 is turned on (the switching transistor M1 is active at high level), the Data voltage on the Data line Data is written into one end of the storage capacitor Cst through a channel between the drain and source electrodes of the switching transistor M1 and simultaneously acts on the gate electrode of the driving transistor M2, the driving transistor M2 is turned on, and the organic light emitting diode OLED is driven to emit light; the second phase is a display maintaining phase, in which the Scan line Scan is at a low level, the switching transistor M1 is turned off, the channel between the Data line Data and the storage capacitor Cst is turned off, and the driving transistor M2 is turned on under the action of the storage capacitor Cst to maintain the organic light emitting diode OLED emitting light until the next frame time. Wherein, when the organic light emitting diode OLED emits light, the current I flowing through the organic light emitting diode OLEDOLED＝(1/2)Cox(μW/L)(VData-VOLED-VARVSS-Vth)2Wherein, CoxAnd μ, W and L are a unit area channel capacitance, a channel mobility, a channel width and a channel length of the driving transistor, respectivelyDegree, VDataFor the Data voltage on the Data line Data, VOLEDIs the tube voltage drop, V, of an organic light emitting diodeARVSSIs the voltage at the low-voltage end of the DC power supply, VthIs the threshold voltage of the drive transistor.
As can be seen from the above formula, the current I flowing through the organic light emitting diode OLEDOLEDAnd the threshold voltage V of the drive transistorthIs related to the channel mobility mu, wherein the threshold voltage V of the driving transistorthThere is an instability during the lifetime of the drive transistor and the channel mobility μ degrades over time, so both will contribute to the current I flowing through the organic light emitting diode OLEDOLEDThis has an effect on the display, which in turn causes display unevenness.
In order to effectively solve the above-mentioned problems, the present invention provides a pixel circuit, by which threshold voltage compensation and mobility compensation for a driving transistor can be simultaneously performed to ensure uniformity of display.
Fig. 2 is a block schematic diagram of a pixel circuit according to an embodiment of the invention. As shown in fig. 2, the pixel circuit according to the embodiment of the present invention includes: a first power source terminal ELVDD, a dual gate driving transistor DT, a threshold voltage compensating unit 10, a mobility compensating unit 20, and a light emission controlling unit 30.
Wherein, the drain electrode of the double-gate driving transistor DT is electrically connected with the first power supply end ELVDD; the threshold voltage compensation unit 10 is electrically connected to a DATA terminal DATA of an external control unit (not specifically shown in the drawing), a first control terminal G1 of the external control unit, a first gate of the dual gate driving transistor DT, and a source of the dual gate driving transistor DT, respectively; the mobility compensation unit 20 is electrically connected to the detection signal terminal Sense of the external control unit, the second control terminal G2 of the external control unit, and the source of the dual-gate driving transistor DT, respectively; the light emission controlling unit 30 is electrically connected to the DATA terminal DATA of the external controlling unit, the third control terminal G3 of the external controlling unit, the second gate electrode of the dual gate driving transistor DT, the source electrode of the dual gate driving transistor DT, and the light emitting device OLED, respectively. The external control unit controls the threshold voltage compensation unit 10 and the mobility compensation unit 20 through the DATA terminal DATA, the first control terminal G1, the detection signal terminal Sense and the second control terminal G2 to perform threshold voltage compensation on the dual-gate driving transistor DT, and controls the mobility compensation unit 20 and the light emission control unit 30 through the detection signal terminal Sense, the second control terminal G2, the DATA terminal DATA and the third control terminal G3 to perform mobility compensation on the dual-gate driving transistor DT and control the dual-gate driving transistor DT to drive the light emitting device OLED to emit light.
Specifically, in the embodiment of the present invention, a driving transistor structure with a dual gate (referred to as a dual gate driving transistor for short) may be used to replace the original driving transistor, and this kind of transistor may be obtained by modifying the structure of the original driving transistor, for example, a light-shielding metal layer of a top gate of the existing driving transistor may be used as another metal electrode of the driving transistor to form a bottom gate of the dual gate driving transistor, where the top gate is a first gate of the dual gate driving transistor, and the bottom gate is a second gate of the dual gate driving transistor. Then, threshold voltage compensation and mobility compensation are respectively carried out by utilizing two grids of the double-grid driving transistor, so that the simultaneous compensation of the threshold voltage and the mobility is realized.
For example, one frame time of the pixel circuit display may be divided into a plurality of stages, in one of the stages, the threshold voltage compensation unit 10 and the mobility compensation unit 20 cooperate with each other, and the threshold voltage compensation for the dual-gate driving transistor DT is implemented by the first gate of the dual-gate driving transistor DT, and in another stage, the mobility compensation unit 20 and the emission control unit 30 cooperate with each other, and the mobility compensation for the dual-gate driving transistor DT is implemented by the second gate of the dual-gate driving transistor DT, and then the light emitting device OLED is controlled to emit light under the combined action of the threshold voltage compensation and the mobility compensation, so that the threshold voltage compensation and the mobility compensation for the dual-gate driving transistor are implemented at the same time, and the uniformity of the display is ensured.
How to perform the threshold voltage compensation and the mobility compensation is described in detail below with reference to specific examples of the present invention.
According to an embodiment of the present invention, as shown in fig. 3, the threshold voltage compensation unit 10 includes: a first transistor T1 and a first capacitor C1, wherein a first electrode of the first transistor T1 is electrically connected to the DATA terminal DATA, and a control electrode of the first transistor T1 is electrically connected to the first control terminal G1; one end of the first capacitor C1 is electrically connected to the second electrode of the first transistor T1 and the first gate of the dual gate driving transistor DT, respectively, and the other end of the first capacitor C1 is electrically connected to the source of the dual gate driving transistor DT.
The mobility compensation unit 20 includes: a first electrode of the second transistor T2, a first electrode of the second transistor T2 is electrically connected to the sensing signal terminal Sense, a control electrode of the second transistor T2 is electrically connected to the second control terminal G2, and a second electrode of the second transistor T2 is electrically connected to the source electrode of the dual gate driving transistor DT and the other end of the first capacitor C1, respectively.
The external control unit further outputs a first DATA voltage Vdata1 to the DATA terminal DATA and outputs a first detection voltage Vsense1 to the detection signal terminal Sense when the first transistor T1 and the second transistor T2 are both controlled to be turned on by the first control terminal G1 and the second control terminal G2, so that the threshold voltage of the dual gate driving transistor DT is stored in the first capacitor C1 under the combined action of the first DATA voltage Vdata1 and the first detection voltage Vsense1 when the first transistor T1 and the second transistor T2 are both controlled to be turned off by the first control terminal G1 and the second control terminal G2.
According to an embodiment of the present invention, the first data voltage Vdata1 is greater than the threshold voltage Vth of the dual gate driving transistor DT, and the first detection voltage Vsense1 is zero.
Specifically, as shown in fig. 3, when detecting the threshold voltage of the dual-gate driving transistor DT, an external control unit (e.g., an IC in a GOA unit) first outputs a high level to the first control terminal G1 and the second control terminal G2, respectively, at which time the first transistor T1 and the second transistor T2 are both turned on, and at the same time the external control unit writes a first DATA voltage Vdata1 (e.g., about 2V, the threshold voltage Vth of the dual-gate driving transistor is generally about 1V) to the DATA terminal DATA, and writes a first detection voltage Vsense1 (e.g., about 0V) to the detection signal terminal Sense, at which time the voltages at two ends of the first capacitor C1 are Vdata1 and Vsense1, respectively. Then, the external control unit outputs a low level to the first control terminal G1 and the second control terminal G2 respectively, at this time, the first transistor T1 and the second transistor T2 are both turned off, the other terminal voltage of the first capacitor C1 starts to be gradually charged to Vdata1-Vth-Vsense1 (when the first detection voltage Vsense1 is 0V, the other terminal voltage of the first capacitor C1 is Vdata1-Vth), and the voltage in the first capacitor C1 is stored as Vth, that is, the threshold voltage Vth of the dual-gate driving transistor DT is stored in the first capacitor C1, so that the threshold voltage data does not need to be written back, and the threshold voltage compensation of the dual-gate driving transistor can be realized through the voltage stored in the first capacitor C1.
It should be noted that in the embodiment of the present invention, the threshold voltage Vth of the dual-gate driving transistor DT may also be stored in the first capacitor C1 through the first power source terminal ELVDD, but this approach may cause a problem of long threshold voltage detection time. Specifically, when the first detection voltage Vsense1, for example, 0V, is input through the second transistor T2 and the first data voltage Vdata1, for example, 2V, is input through the first transistor T1 when the threshold voltage of the dual-gate driving transistor DT is detected, the gate-source voltage Vgs of the dual-gate driving transistor DT becomes 2V, and the gate voltage of the dual-gate driving transistor DT drops by about 1V, so that the dual-gate driving transistor DT is in the critical conduction state. However, if the initial value of the gate voltage is written from the first power source terminal ELVDD, i.e., 24V, it needs to be decreased by about 23V to make the dual gate driving transistor DT in the critical conducting state, which takes a long time. Therefore, the initial set voltage written by the DATA terminal DATA is about 2V, so that the time for detecting the threshold voltage can be greatly reduced, and the power consumption in detecting the panel threshold voltage is further reduced.
In addition, when the threshold voltage of the first gate of the dual gate driving transistor DT is detected, the second gate of the dual gate driving transistor DT needs to be in a non-interference state. For example, the conductive particles in the semiconductor layer (e.g., IGZO layer) of the dual gate driving transistor DT are all in an unstressed natural state before the threshold voltage detection, and if the voltage difference between the second gate and the source applies a value greater than the threshold voltage in the threshold voltage detection process, the conductive particles in the semiconductor layer are already in a stressed moving state before the threshold voltage detection, which may affect the accuracy of the threshold voltage detection. Because the threshold voltage detection needs to utilize the voltage difference to activate the directional motion of a part of particles, but because the voltage difference exists between the second gate and the source, so that a part of particles are already in a motion state, the voltage difference between the first gate and the source required for activating the directional motion of the particles changes, and the threshold voltage detection is inaccurate.
Therefore, in the embodiment of the invention, the second gate of the dual-gate driving transistor has no voltage initially, so that the second gate is not influenced in the process of forming the voltage difference of the threshold voltage magnitude between the first gate and the source, so that the accurate threshold voltage can be obtained, and the threshold voltage is always stored in the first capacitor, so that the threshold voltage compensation of the dual-gate driving transistor can be realized without writing back the threshold voltage data.
According to an embodiment of the present invention, as shown in fig. 3, the light emission control unit 30 includes: a third transistor T3 and a second capacitor C2, wherein a first electrode of the third transistor T3 is electrically connected to the DATA terminal DATA, and a control electrode of the third transistor T3 is electrically connected to the third control terminal G3; one end of the second capacitor C2 is electrically connected to the second electrode of the third transistor T3 and the second gate electrode of the dual gate driving transistor DT, respectively, and the other end of the second capacitor C2 is electrically connected to the source electrode of the dual gate driving transistor DT and one end of the light emitting device OLED, which is electrically connected to the second power source terminal ELVSS.
When the external control unit controls the second transistor T2 and the third transistor T3 to be turned on through the second control terminal G2 and the third control terminal G3, the external control unit further outputs a second DATA voltage Vdata2 to the DATA terminal DATA and keeps a first preset time, and outputs a second detection voltage Vsense2 to the detection signal terminal Sense within the first preset time, and then makes the detection signal terminal Sense in a floating state to charge the detection signal terminal Sense; the external control unit further detects a charging voltage of the detection signal terminal Sense when the second transistor T2 and the third transistor T3 are controlled to be turned off by the second control terminal G2 and the third control terminal G3, obtains a mobility according to the charging voltage, and obtains a mobility compensation value according to the mobility; when the external control unit controls the second transistor T2 and the third transistor T3 to be turned on through the second control terminal G2 and the third control terminal G3, the external control unit also writes a mobility compensation value into the source of the dual gate driving transistor DT and writes a third data voltage Vdata3 into the second gate of the dual gate driving transistor DT to perform mobility compensation on the dual gate driving transistor DT while controlling the light emitting device OLED to emit light.
According to an embodiment of the present invention, the sum of the second data voltage Vdata2 and the second detection voltage Vsense2 is less than a voltage required for the light emitting device OLED to emit light.
Specifically, as shown in fig. 3, when performing mobility detection on the dual-gate driving transistor DT, the external control unit first outputs a high level to the second control terminal G2 and the third control terminal G3, at which time the second transistor T2 and the third transistor T3 are both turned on, and at the same time the external control unit writes the second DATA voltage Vdata2 (e.g., about 3V) to the DATA terminal DATA and keeps the DATA terminal DATA for a first preset time, and writes the second detection voltage Vsense2 (e.g., about 0V) to the detection signal terminal Sense within the first preset time, and then makes the detection signal terminal Sense in a floating state (floating state), at which time the detection signal terminal Sense starts to be charged, i.e., starts to be charged to the detection signal Line (Sense Line).
Then, the external control unit outputs a low level to the second control terminal G2 and the third control terminal G3 respectively, at this time, the second transistor T2 and the third transistor T3 are turned off, and the external control unit detects the charging voltage of the detection signal terminal Sense, obtains the mobility according to the charging voltage, and obtains the mobility compensation value according to the mobility (specifically, the mobility compensation value can be obtained by using the prior art, and details are not described here).
Finally, the external control unit outputs a high level to the second control terminal G2 and the third control terminal G3 again, at this time, the second transistor T2 and the third transistor T3 are both turned on, and simultaneously, the external control unit writes the third DATA voltage Vdata3 to the DATA terminal DATA, and writes a voltage (i.e., mobility compensation voltage) corresponding to the mobility compensation value to the detection signal terminal Sense, and under the action of the third DATA voltage Vdata3, the mobility compensation voltage, and the threshold voltage Vth stored in the first capacitor C1, the light emission control of the light emitting device OLED and the threshold voltage compensation and mobility compensation of the dual gate driving transistor DT are realized.
The operation of the pixel circuit shown in fig. 3 is further described with reference to fig. 4.
As shown in fig. 4, during one frame time displayed by the pixel circuit, the following five stages can be included:
first phase t1 (reset phase): the first control terminal G1 and the second control terminal G2 are both at a high level, the first transistor T1 and the second transistor T2 are both turned on, the detection signal terminal Sense is written with a first detection voltage Vsense1 (also referred to as a set voltage Vsense1, generally 0V), and the DATA terminal DATA is written with a first DATA voltage Vdata1 (also referred to as a DATA voltage Vdata1, generally 2V).
Second stage t2 (threshold voltage storage stage): the first control terminal G1, the second control terminal G2, and the third control terminal G3 are all low, the first transistor T1, the second transistor T2, and the third transistor T3 are all turned off, the voltage of the other end of the first capacitor C1 starts to be charged to Vdata1-Vth, and the voltage stored in the first capacitor C1 is Vth.
Third stage t3 (mobility detection stage): the second control terminal G2 and the third control terminal G3 are both at a high level, the second transistor T2 and the third transistor T3 are both turned on, the DATA terminal DATA is written with a second DATA voltage Vdata2 (generally 3V) for mobility detection, and the detection signal terminal Sense is first written with a second detection voltage Vsense2, i.e., an initial voltage (generally 0V), and then floated, at which time the detection signal terminal Sense starts to charge. It should be noted that, in each frame time, the written second data voltage Vdata2 is the same and the written time is the same, so the voltage difference detected at the detection signal terminal Sense is the mobility difference.
Fourth stage t4 (charging voltage acquisition stage): the first control terminal G1, the second control terminal G2, and the third control terminal G3 are all low level, the first transistor T1, the second transistor T2, and the third transistor T3 are all turned off, the charge voltage is obtained by detecting the signal terminal Sense, the charge voltage is compared with the standard voltage stored in the memory in the external control unit, the mobility change condition can be obtained, and then the mobility compensation value can be obtained through a corresponding algorithm according to the mobility change condition.
Fifth stage t5 (write back data stage): the second control terminal G2 and the third control terminal G3 are both high level, the second transistor T2 and the third transistor T3 are both turned on, the DATA terminal DATA is written into a third DATA voltage Vdata3 for light emission of the light emitting device OLED, the detection signal terminal Sense is written into a mobility compensation voltage corresponding to the mobility compensation value, and meanwhile, since the voltage difference between the two ends of the first capacitor C1 is constant, the threshold voltage Vth of the dual-gate driving transistor DT is fixed, so that when the light emitting device OLED emits light, threshold voltage compensation and mobility compensation can be simultaneously performed on the dual-gate driving transistor DT, and uniformity of display is ensured.
That is to say, in the embodiment of the present invention, a dual-gate driving transistor structure is adopted, and a dual-capacitor structure is provided to store the threshold voltage Vth and the gate-source voltage Vgs, respectively, so that the threshold voltage and the mobility can be compensated simultaneously, and further, better picture quality is obtained, and the compensation of the threshold voltage does not require to write back the threshold voltage data, which greatly saves the compensation time, increases the display time, and the whole pixel circuit has a simple structure and a simple control timing sequence, and greatly reduces the production cost and the complexity of control, etc.
In addition, in the above embodiment, the first transistor T1, the second transistor T2, and the third transistor T3 are all transistors with high level being active, for example, they may be P-type TFT transistors with high level being active, but in other embodiments of the present invention, transistors with low level being active may also be used, and it is not limited herein, but only when controlling, the input levels of the corresponding control terminals are opposite.
In summary, according to the pixel circuit of the embodiment of the invention, the drain of the dual-gate driving transistor is electrically connected to the first power source terminal, the threshold voltage compensation unit is electrically connected to the data terminal of the external control unit, the first control terminal of the external control unit, the first gate of the dual-gate driving transistor and the source of the dual-gate driving transistor, the mobility compensation unit is electrically connected to the detection signal terminal of the external control unit, the second control terminal of the external control unit and the source of the dual-gate driving transistor, and the light-emitting control unit is electrically connected to the data terminal of the external control unit, the third control terminal of the external control unit, the second gate of the dual-gate driving transistor, the source of the dual-gate driving transistor and the light-emitting device. The external control unit controls the threshold voltage compensation unit and the mobility compensation unit through the data end, the first control end, the detection signal end and the second control end to compensate the threshold voltage of the double-gate driving transistor, controls the mobility compensation unit and the light-emitting control unit through the detection signal end, the second control end, the data end and the third control end to compensate the mobility of the double-gate driving transistor and controls the double-gate driving transistor to drive the light-emitting device to emit light. Therefore, the threshold voltage compensation and the mobility compensation of the driving transistor can be realized simultaneously, the problem of uneven display caused by threshold voltage drift and mobility change is effectively solved, and the compensation mode is simple and reliable.
Fig. 5 is a block schematic diagram of a display device according to an embodiment of the present invention. As shown in fig. 5, a display device 1000 according to an embodiment of the invention includes the pixel circuit 100.
According to the display device provided by the embodiment of the invention, through the pixel circuit, the threshold voltage compensation and the mobility compensation of the driving transistor can be realized at the same time, the problem of uneven display caused by threshold voltage drift and mobility change is effectively solved, and the compensation mode is simple and reliable.
Fig. 6 is a schematic structural diagram of a double gate driving transistor according to an embodiment of the present invention. As shown in fig. 6, the dual gate driving transistor of the embodiment of the present invention includes: a light-shielding metal layer 201, a buffer layer 202, an organic semiconductor layer 203, an insulating layer 204, a gate layer 205, a hole-punched layer 206, a source layer S, and a drain layer D.
Wherein, the light-shielding metal layer 201 is disposed on the substrate 300 (the substrate 300 may be glass), and the light-shielding metal layer 201 is used as a second gate (also called bottom gate) of the dual-gate driving transistor; the buffer layer 202 is arranged on the light-shielding metal layer 201 and the substrate 300, and the buffer layer 202 is a non-metal layer; the organic semiconductor layer 203 is disposed on the buffer layer 202; an insulating layer 204 is provided on the organic semiconductor layer 203; a gate layer 205 is disposed on the insulating layer 204, the gate layer 205 serves as a first gate (also referred to as a top gate) of the dual-gate driving transistor, and the gate layer 205 is a metal layer; a punching layer 206 is disposed on the buffer layer 202, the organic semiconductor layer 203, the insulating layer 204, and the gate electrode layer 205, the punching layer 206 includes a first through-hole a1 and a second through-hole a2, the punching layer 206 is an inorganic layer through which punching is performed; the source layer S and the drain layer D are respectively disposed on the perforated layer 206, and the source layer S communicates with one end of the organic semiconductor layer 203 through the first through hole a1, and the drain layer D communicates with the other end of the organic semiconductor layer 203 through the second through hole a 2.
In the dual-gate driving transistor shown in fig. 6, the gate layer 205 is used as one metal gate of the dual-gate driving transistor to form a first gate, i.e. a top gate, of the dual-gate driving transistor, and the light-shielding metal layer 201 is used as the other metal gate of the dual-gate driving transistor to form a second gate, i.e. a bottom gate, of the dual-gate driving transistor, and a specific two-gate driving transistor can be obtained by this structure.
As can be seen from the structure of the dual-gate driving transistor shown in fig. 6, the dual-gate driving transistor can be directly obtained by improving the existing single-gate driving transistor, that is, the gate of the original driving transistor is used as one gate of the dual-gate driving transistor, and the original light-shielding metal layer is used as the other gate of the dual-gate driving transistor, so that the driving transistor with two gates can be obtained, thereby greatly reducing the development and production costs of the dual-gate driving transistor, and compared with the driving transistor with two driving transistors connected in series to realize the dual-gate function, the structure of the whole transistor is effectively reduced, and the occupied area is reduced.
According to the double-gate driving transistor provided by the embodiment of the invention, the gate layer is used as one gate of the double-gate driving transistor, and the light-shielding metal layer is used as the other gate of the double-gate driving transistor, so that the development cost and the production cost of the double-gate driving transistor are greatly reduced, and compared with the double-gate driving transistor which is realized by two driving transistors connected in series, the double-gate driving transistor effectively reduces the structure of the whole transistor and reduces the occupied area.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims (8)

1. A pixel circuit, comprising: a first power supply terminal, a dual gate driving transistor, a threshold voltage compensation unit, a mobility compensation unit, and a light emission control unit,
the drain electrode of the double-gate driving transistor is electrically connected with the first power supply end;
the threshold voltage compensation unit is electrically connected with a data end of an external control unit, a first control end of the external control unit, a first grid electrode of the double-grid driving transistor and a source electrode of the double-grid driving transistor respectively;
the mobility compensation unit is electrically connected with a detection signal end of the external control unit, a second control end of the external control unit and a source electrode of the double-gate drive transistor respectively;
the light-emitting control unit is electrically connected with the data end of the external control unit, the third control end of the external control unit, the second grid electrode of the double-grid driving transistor, the source electrode of the double-grid driving transistor and the light-emitting device respectively,
wherein the content of the first and second substances,
the external control unit controls the threshold voltage compensation unit and the mobility compensation unit through the data terminal, the first control terminal, the detection signal terminal and the second control terminal to perform threshold voltage compensation on the dual-gate driving transistor, and controls the mobility compensation unit and the light emission control unit through the detection signal terminal, the second control terminal, the data terminal and the third control terminal to perform mobility compensation on the dual-gate driving transistor and control the dual-gate driving transistor to drive the light emitting device to emit light, wherein the mobility compensation unit includes:
a second transistor, a first electrode of the second transistor is electrically connected to the detection signal terminal, a control electrode of the second transistor is electrically connected to the second control terminal, and a second electrode of the second transistor is electrically connected to a source electrode of the dual-gate driving transistor and the other end of the first capacitor, respectively, wherein the dual-gate driving transistor includes:
the shading metal layer is arranged on the substrate and is used as a second grid electrode of the double-grid driving transistor;
a buffer layer disposed on the light-shielding metal layer and the substrate;
an organic semiconductor layer disposed on the buffer layer;
an insulating layer disposed on the organic semiconductor layer;
a gate layer disposed on the insulating layer, the gate layer serving as a first gate of the dual gate driving transistor;
a via layer disposed on the buffer layer, the organic semiconductor layer, the insulating layer, and the gate layer, the via layer including a first via and a second via;
the source electrode layer and the drain electrode layer are respectively arranged on the hole punching layer, the source electrode layer is communicated with one end of the organic semiconductor layer through the first through hole, and the drain electrode layer is communicated with the other end of the organic semiconductor layer through the second through hole.
2. The pixel circuit according to claim 1, wherein the threshold voltage compensation unit includes:
a first transistor, a first electrode of which is electrically connected to the data terminal, and a control electrode of which is electrically connected to the first control terminal;
and one end of the first capacitor is electrically connected with the second pole of the first transistor and the first grid electrode of the double-grid driving transistor respectively, and the other end of the first capacitor is electrically connected with the source electrode of the double-grid driving transistor.
3. The pixel circuit according to claim 2, wherein the external control unit further outputs a first data voltage to the data terminal and a first sensing voltage to the sensing signal terminal when both the first transistor and the second transistor are controlled to be turned on by the first control terminal and the second control terminal, so as to store a threshold voltage of the dual gate driving transistor to the first capacitor under a combined action of the first data voltage and the first sensing voltage when both the first transistor and the second transistor are controlled to be turned off by the first control terminal and the second control terminal.
4. The pixel circuit of claim 3, wherein the first data voltage is greater than a threshold voltage of the dual gate drive transistor, and the first detection voltage is zero.
5. The pixel circuit according to claim 2, wherein the light emission control unit includes:
a third transistor, a first electrode of which is electrically connected to the data terminal, and a control electrode of which is electrically connected to the third control terminal;
and one end of the second capacitor is electrically connected with the second pole of the third transistor and the second grid electrode of the double-grid driving transistor respectively, the other end of the second capacitor is electrically connected with the source electrode of the double-grid driving transistor and one end of the light-emitting device, and the other end of the light-emitting device is electrically connected with a second power supply end.
6. The pixel circuit according to claim 5,
when the external control unit controls the second transistor and the third transistor to be conducted through the second control end and the third control end, the external control unit also outputs a second data voltage to the data end and keeps a first preset time, and outputs a second detection voltage to the detection signal end firstly within the first preset time, and then the detection signal end is in a suspended state so as to charge the detection signal end;
when the external control unit controls the second transistor and the third transistor to be disconnected through the second control end and the third control end, the external control unit also detects the charging voltage of the detection signal end, obtains the mobility according to the charging voltage, and obtains a mobility compensation value according to the mobility;
when the external control unit controls the second transistor and the third transistor to be conducted through the second control end and the third control end, the mobility compensation value is written into the source electrode of the double-gate driving transistor, and third data voltage is written into the second gate electrode of the double-gate driving transistor, so that the mobility compensation is carried out on the double-gate driving transistor while the light-emitting device is controlled to emit light.
7. The pixel circuit according to claim 6, wherein a sum of the second data voltage and the second detection voltage is less than a voltage required for the light emitting device to emit light.
8. A display device comprising the pixel circuit according to any one of claims 1 to 7.
CN201711204071.3A 2017-11-27 2017-11-27 Pixel circuit, display device and double-gate driving transistor Active CN107767814B (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201711204071.3A CN107767814B (en) 2017-11-27 2017-11-27 Pixel circuit, display device and double-gate driving transistor
US15/981,020 US10777128B2 (en) 2017-11-27 2018-05-16 Pixel circuitry with mobility compensation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201711204071.3A CN107767814B (en) 2017-11-27 2017-11-27 Pixel circuit, display device and double-gate driving transistor

Publications (2)

Publication Number Publication Date
CN107767814A CN107767814A (en) 2018-03-06
CN107767814B true CN107767814B (en) 2020-02-21

Family

ID=61275992

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201711204071.3A Active CN107767814B (en) 2017-11-27 2017-11-27 Pixel circuit, display device and double-gate driving transistor

Country Status (2)

Country Link
US (1) US10777128B2 (en)
CN (1) CN107767814B (en)

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108281105B (en) 2018-03-30 2021-02-05 京东方科技集团股份有限公司 Scanning signal adjusting method and device and display device
CN109119025B (en) * 2018-09-28 2021-04-06 京东方科技集团股份有限公司 Voltage compensation method and device and display panel
CN109119026B (en) * 2018-09-29 2020-06-23 京东方科技集团股份有限公司 Pixel circuit data signal compensation method and device and display panel
KR102631125B1 (en) * 2018-10-30 2024-01-29 엘지디스플레이 주식회사 Pixel and light emitting display apparatus comprising the same
CN109727578A (en) * 2018-12-14 2019-05-07 合肥鑫晟光电科技有限公司 Compensation method, device and the display equipment of display device
CN109686332B (en) * 2019-01-24 2021-04-30 合肥鑫晟光电科技有限公司 Compensation module, logic gate circuit, gate drive circuit and display device
CN110264957B (en) * 2019-06-24 2021-01-26 京东方科技集团股份有限公司 Pixel circuit compensation method and device and display equipment
CN110288947A (en) * 2019-06-28 2019-09-27 京东方科技集团股份有限公司 A kind of pixel circuit and its driving method, display device
CN110415648A (en) * 2019-07-16 2019-11-05 深圳市华星光电半导体显示技术有限公司 GOA circuit
CN110517641B (en) * 2019-08-30 2021-05-14 京东方科技集团股份有限公司 Pixel circuit, parameter detection method, display panel and display device
CN110707095A (en) * 2019-09-04 2020-01-17 深圳市华星光电半导体显示技术有限公司 Display panel
CN111179850A (en) * 2020-01-13 2020-05-19 深圳市华星光电半导体显示技术有限公司 Pixel compensation circuit, array substrate and display panel
US10916197B1 (en) * 2020-02-14 2021-02-09 Shenzhen China Star Optoelectronics Semiconductor Display Technology Co., Ltd. Pixel compensation circuit and display panel
CN111261110A (en) * 2020-03-09 2020-06-09 深圳市华星光电半导体显示技术有限公司 AMOLED pixel driving circuit, pixel driving method and display panel
CN117975879A (en) 2020-10-20 2024-05-03 厦门天马微电子有限公司 Display panel, driving method and display device
CN112511769B (en) * 2020-11-05 2022-09-20 北京大学深圳研究生院 Image sensor pixel circuit and image sensing array
KR20220092315A (en) * 2020-12-24 2022-07-01 엘지디스플레이 주식회사 Display device and driving method trherof
CN112562590A (en) * 2020-12-30 2021-03-26 深圳市华星光电半导体显示技术有限公司 Pixel driving circuit and display device
CN114765007A (en) * 2021-01-04 2022-07-19 京东方科技集团股份有限公司 Display device, pixel circuit and driving method thereof
CN113674673B (en) * 2021-08-19 2023-10-31 深圳市华星光电半导体显示技术有限公司 Display panel driving circuit, display panel and display terminal
KR20230094791A (en) * 2021-12-21 2023-06-28 엘지디스플레이 주식회사 Display device
CN114373414B (en) * 2022-01-18 2023-06-02 深圳市华星光电半导体显示技术有限公司 Display panel electrical property detection circuit and display panel
CN114694589A (en) * 2022-05-06 2022-07-01 京东方科技集团股份有限公司 Pixel driving circuit and method and display panel
CN114842801B (en) * 2022-06-28 2022-09-20 惠科股份有限公司 Pixel driving circuit, display panel and display device
CN115311982A (en) * 2022-08-30 2022-11-08 武汉天马微电子有限公司 Display panel, driving method thereof and display device
CN117594009A (en) * 2023-12-28 2024-02-23 惠科股份有限公司 Organic light emitting display device and driving method thereof

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7612749B2 (en) * 2003-03-04 2009-11-03 Chi Mei Optoelectronics Corporation Driving circuits for displays
KR100893482B1 (en) 2007-08-23 2009-04-17 삼성모바일디스플레이주식회사 Organic Light Emitting Display and Driving Method Thereof
JP6570825B2 (en) * 2013-12-12 2019-09-04 株式会社半導体エネルギー研究所 Electronics
KR102091485B1 (en) * 2013-12-30 2020-03-20 엘지디스플레이 주식회사 Organic light emitting display device and method for driving thereof
US9934723B2 (en) * 2014-06-25 2018-04-03 Lg Display Co., Ltd. Thin film transistor substrate, display panel including the same, and method of manufacturing the same
KR102241704B1 (en) * 2014-08-07 2021-04-20 삼성디스플레이 주식회사 Pixel circuit and organic light emitting display device having the same
US10262570B2 (en) * 2015-03-05 2019-04-16 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and method for driving the same
CN104732927B (en) 2015-04-09 2017-10-03 京东方科技集团股份有限公司 A kind of image element circuit and its driving method and display device
US9666655B2 (en) * 2015-05-05 2017-05-30 Semiconductor Energy Laboratory Co., Ltd. Display device
KR102570832B1 (en) * 2016-05-23 2023-08-24 엘지디스플레이 주식회사 Organic light emitting diode display device and driving method the same
CN106910459B (en) * 2017-04-26 2019-01-25 上海天马有机发光显示技术有限公司 A kind of organic light emitting display panel, its driving method and display device
CN107134261B (en) * 2017-06-28 2019-07-12 武汉华星光电半导体显示技术有限公司 Pixel circuit and its control method, display panel
US10262595B2 (en) 2017-06-28 2019-04-16 Wuhan China Star Optoelectronics Semiconductor Display Technology Co., Ltd. Pixel circuit, control method thereof, and display panel
CN107358915B (en) * 2017-08-11 2020-01-07 上海天马有机发光显示技术有限公司 Pixel circuit, driving method thereof, display panel and display device

Also Published As

Publication number Publication date
US10777128B2 (en) 2020-09-15
US20190164476A1 (en) 2019-05-30
CN107767814A (en) 2018-03-06

Similar Documents

Publication Publication Date Title
CN107767814B (en) Pixel circuit, display device and double-gate driving transistor
US10170042B2 (en) Display device having shared column lines
US9443466B2 (en) Organic light emitting diode display device having repair circuit coupled to pixels of the display device
US7420530B2 (en) Pixel circuit, display device method for controlling pixel circuit
US9852685B2 (en) Pixel circuit and driving method thereof, display apparatus
US20170186782A1 (en) Pixel circuit of active-matrix light-emitting diode and display panel having the same
US20190019452A1 (en) Pixel circuit, pixel, and amoled display device comprising pixel and driving method thereof
US10621916B2 (en) Driving circuit and driving method thereof, and display device
US11282444B2 (en) Light emitting display apparatus and method for driving thereof
KR102343894B1 (en) Display device
US9548024B2 (en) Pixel driving circuit, driving method thereof and display apparatus
WO2016173124A1 (en) Pixel circuit, driving method and related device thereof
WO2016086627A1 (en) Pixel driving circuit, pixel driving method and display device
WO2016078282A1 (en) Pixel unit driving circuit and method, pixel unit, and display device
JP4547605B2 (en) Display device and driving method thereof
US20170162114A1 (en) Display device and method for driving same
CN105405402A (en) Pixel circuit, drive method thereof, OLED display panel and display device
CN113366562A (en) Pixel unit, array substrate and display terminal
JP5121124B2 (en) Organic EL pixel circuit
KR20160074772A (en) Organic light emitting display device and method for driving thereof
CN114677967B (en) Display device and driving method thereof
US10600364B2 (en) Display panel, pixel compensation circuit, and method for controlling the same

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant